Very high doses of iron can be fatal, particularly if taken by children, so always keep iron supplements out of the reach of children. Most people should be able to get all the iron they need by eating a varied and balanced diet. If you take iron supplements, do not take too much as this could be harmful. Taking 17mg or less a day of iron supplements is unlikely to cause any harm.
Its absorption can be enhanced with organic acids, such as vitamin C, but is decreased by plant compounds like phytate. Bottom Line: Iron is an essential dietary mineral that plays an important role in transporting oxygen throughout the body.
Regulation of Iron Stores. There are two reasons why iron levels are tightly regulated within the body: Iron is an essential nutrient that plays a role in many basic body functions, so we must get a small amount.
High levels of iron are potentially toxic, so we should avoid getting too much. On the other hand, conditions that stimulate hepcidin formation may cause iron deficiency. Bottom Line: The rate of iron absorption from the digestive tract is tightly regulated by the hormone hepcidin.
Iron Toxicity. Iron toxicity can be either sudden or gradual. Under normal circumstances, very little free iron circulates in the bloodstream.
It is safely bound to proteins, such as transferrin, which keep it from causing harm. Several conditions may cause this to happen. These include: Iron poisoning: Poisoning can occur when people, usually children, overdose on iron supplements 5 , 6.
Hereditary hemochromatosis: A genetic disorder characterized by excessive absorption of iron from food 7. African iron overload: A type of dietary iron overload caused by high levels of iron in food or drinks. It was first observed in Africa, where homemade beer was brewed in iron pots 8. Early symptoms of iron poisoning may include stomach pain, nausea and vomiting. Bottom Line: Iron toxicity refers to the harmful effects of excess iron. Iron Overload.
If you are prone to iron overload, you can minimize the risk of health problems by: Reducing your intake of iron-rich foods, such as red meat. Donating blood regularly. Avoiding taking vitamin C with foods that are rich in iron. Avoid using iron cookware. Bottom Line: Iron overload is characterized by excessive amounts of iron in the body. Iron and Cancer Risk. Bottom Line: Iron overload disorders have been linked with an increased risk of cancer.
Iron and Risk of Infection. There are two reasons for this 21 : The immune system uses iron to kill harmful bacteria, so some amount of iron is needed to fight infections. Elevated levels of free iron stimulate the growth of bacteria and viruses, so too much iron can have the opposite effect and increase the risk of infections. Bottom Line: Iron overload and high-dose iron supplementation may increase the risk of infection in certain individuals. Take Home Message.
Food sources of iron include red meat, liver, poultry, seafood, iron-fortified cereals, whole grains, eggs, dried fruit, beans, tofu, nuts and green leafy vegetables. Animal sources of iron are better absorbed by your body, but eating foods containing vitamin C or eating animal sources of iron along with plant-based sources increases the amount of iron that your body absorbs.
Men and women over 50 need at least 8 milligrams of iron per day, while women 50 and under need at least 18 milligrams of iron per day. You shouldn't consume more than 45 milligrams of iron per day from supplements or food, as this could cause toxicity symptoms. People with hemochromatosis need to follow a low-iron diet and only consume the amount of iron recommended by their doctor.
Iron in food comes in two forms: heme iron and nonheme iron. Nonheme iron is found in plant foods and iron-fortified food products. Meat, seafood, and poultry have both heme and nonheme iron. Your body absorbs iron from plant sources better when you eat it with meat, poultry, seafood, and foods that contain vitamin C , such as citrus fruits, strawberries, sweet peppers, tomatoes, and broccoli. Iron is available in many multivitamin-mineral supplements and in supplements that contain only iron.
Iron in supplements is often in the form of ferrous sulfate, ferrous gluconate, ferric citrate, or ferric sulfate. Dietary supplements that contain iron have a statement on the label warning that they should be kept out of the reach of children. Accidental overdose of iron-containing products is a leading cause of fatal poisoning in children under 6.
Most people in the United States get enough iron. However, certain groups of people are more likely than others to have trouble getting enough iron:. In the short term, getting too little iron does not cause obvious symptoms. The body uses its stored iron in the muscles, liver, spleen, and bone marrow. But when levels of iron stored in the body become low, iron deficiency anemia sets in. Red blood cells become smaller and contain less hemoglobin.
As a result, blood carries less oxygen from the lungs throughout the body. Symptoms of iron deficiency anemia include GI upset, weakness, tiredness, lack of energy, and problems with concentration and memory. In addition, people with iron deficiency anemia are less able to fight off germs and infections , to work and exercise, and to control their body temperature. Infants and children with iron deficiency anemia might develop learning difficulties.
Iron deficiency is not uncommon in the United States, especially among young children, women under 50, and pregnant women. It can also occur in people who do not eat meat, poultry, or seafood; lose blood; have GI diseases that interfere with nutrient absorption; or eat poor diets.
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